Synthesis and Enzyme Substrate Activity of p-Nitrophenyl N,N'-Diacetyl-4-thio-β-chitobioside

Abstract

Based on the resistance of glycosidase to the hydrolysis of glycosidase, the probe molecule p-nitrophenyl N,N'diacetyl-4-thio-β-chitobioside (pNP-TCB) was designed and synthesized. The effects of pNP-TCB on the degradation of glycoside hydrolase family 18 (GH18) chitinase and 20 (GH20) β-N-acetylhexosaminidase were studied. The results showed that when pNP-TCB was combined with β-N-acetylhexosaminidase, the disaccharide substrate was hardly degraded. But when it reacted with chitinase, the pNP-TCB was degraded by enzyme to release p-nitrophenol group, and the corresponding ultraviolet absorption value can be detected by enzyme-labeled instrument at 405 nm. It indicates that the substrate molecule exhibits good specificity, which can be used to study the properties of GH18 chitinase at the cellular level without interference of β-N-acetylhexosaminidase. The pNP-TCB can also provide a good detection method for screening and isolation between the GH18 chitinase and the GH20 β-N-acetyl hexose.